Tungsten and molybdenum based alloys containing carbon that are sintered under hydrogen undergo decarburization through methane formation. Additionally, if oxygen is present, stable oxides are formed by the oxidation of the alloying elements that are normally present such as titanium, zirconium and hafnium. Stable oxides are formed during sintering because oxygen replaces the carbon in the carbides. This lessens the strengthening power of the alloy system. It is believed therefore that the method of preventing decarburization and eliminating the oxygen available for the formation of stable oxides from the alloying elements would be an advancement in the arts.